Institute of Cytology RAS, Tikhoretsky Ave 4, St. Petersburg, 194064, Russia.
City Clinical Hospital №31, Dynamo ave 3, St. Petersburg, 197110, Russia.
Biochem Biophys Res Commun. 2020 Oct 15;531(2):133-139. doi: 10.1016/j.bbrc.2020.07.064. Epub 2020 Aug 8.
Insulin-like growth factor binding protein 3 (IGFBP3) is a multifunctional protein, able either to stimulate the cell growth or to promote apoptosis. In particular, IGFBP3 plays significant role in propagation of stress-induced senescence in human endometrium-derived mesenchymal stem cells (MESCs) (Vassilieva et al., 2020). We undertook CRISPR/Cas9-mediated IGFBP3 knockout in an effort to decelerate stress-induced senescence in MESCs, but, unexpectedly, IGFBP3-knockout MESCs culture acquired chondrocyte-like features, such as cell condensation and aggregation. We revealed that IGFBP3-knockout MESCs completely lost CD73 and CD90 MESCs positive surface markers, and significantly decreased expression of CD105 and CD146 MESCs positive surface markers. In addition, we found IGFBP3-knockout MESCs aggregates positively stained for Alcian Blue. We also detected expression of collagen type II in IGFBP3-knockout MESCs. The obtained results indicate that MESCs lost stemness after IGFBP3-knockout and underwent differentiation toward chondrogenic lineage. Our findings can enlighten IGFBP3 role in regulation of MESCs chondrogenesis.
胰岛素样生长因子结合蛋白 3（IGFBP3）是一种多功能蛋白，既能刺激细胞生长，又能促进细胞凋亡。特别是，IGFBP3 在人类子宫内膜间充质干细胞（MESCs）应激诱导衰老的发生中起着重要作用（Vassilieva 等人，2020 年）。我们采用 CRISPR/Cas9 介导的 IGFBP3 基因敲除方法，试图减缓 MESCs 的应激诱导衰老，但出乎意料的是，IGFBP3 基因敲除的 MESCs 培养物获得了软骨细胞样特征，如细胞凝聚和聚集。我们发现 IGFBP3 基因敲除的 MESCs 完全丧失了 CD73 和 CD90 MESCs 阳性表面标志物，并且 CD105 和 CD146 MESCs 阳性表面标志物的表达显著降低。此外，我们发现 IGFBP3 基因敲除的 MESCs 聚集物对阿利新蓝呈阳性染色。我们还检测到 IGFBP3 基因敲除的 MESCs 中表达了 II 型胶原蛋白。这些结果表明，IGFBP3 基因敲除后 MESCs 失去了干性并向软骨细胞谱系分化。我们的研究结果可以阐明 IGFBP3 在调控 MESCs 软骨生成中的作用。
